76721328 has 60 divisors (see below), whose sum is σ = 216314280. Its totient is φ = 25383168.

The previous prime is 76721287. The next prime is 76721339. The reversal of 76721328 is 82312767.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 76721292 and 76721301.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18100 + ... + 21932.

It is an arithmetic number, because the mean of its divisors is an integer number (3605238).

Almost surely, 2^76721328 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 76721328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108157140).

76721328 is an abundant number, since it is smaller than the sum of its proper divisors (139592952).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

76721328 is a wasteful number, since it uses less digits than its factorization.

76721328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3986 (or 3977 counting only the distinct ones).

The product of its digits is 28224, while the sum is 36.

The square root of 76721328 is about 8759.0711836359. The cubic root of 76721328 is about 424.9182366355.

The spelling of 76721328 in words is "seventy-six million, seven hundred twenty-one thousand, three hundred twenty-eight".